Use the traditional Maildir format for storing mail. Make the MDA/LDA store it under the Tahoe-LAFS $BASEDIR directory on the mail server so it can be accessed from multiple different MSSs and MUAs. Set up Tahoe-LAFS "dumb" storage servers at the mail site and the lounge. Configure additional storage servers wherever possible (e.g. members can volunteer their server). Tahoe-LAFS storage servers contain only encrypted data, so it doesn't matter who volunteers their space. Only the Tahoe-LAFS gateways (MSS and MUA servers) can decrypt the mail.

+

Use the traditional Maildir format for storing mail. Make the MDA/LDA store it under the Tahoe-LAFS $BASEDIR directory on the mail server so it can be accessed from multiple different MSSs and MUAs. Set up Tahoe-LAFS "dumb" storage servers at the mail site and the lounge. Configure additional storage servers wherever possible (e.g. members can volunteer their server). Tahoe-LAFS storage servers contain only encrypted data, so it doesn't matter who volunteers their space. Only the Tahoe-LAFS '''gateways''' (MSS and MUA servers) can decrypt the mails and securely hand them to authenticated/authorized users.

=== Offline storage ===

=== Offline storage ===

Revision as of 02:04, 11 December 2013

LUG@UCLA plans to move all mail services (including lists) off Google apps. This is a long term project, but the ETA is before Summer 2014.

Contents

Design

KISS. Try to use the least amount of components, and don't overcomplicate the configuration. For example, don't use Maildrop if Dovecot already has an MDA/LDA. Don't use the high-performance sdbox format if Maildir is well supported and tested.

Overview

MTA: Exim

MDA/LDA: Dovecot LDA

MSS: Dovecot

MUA: Roundcube

lists: Mailman

storage format: Maildir

storage redundancy: Tahoe-LAFS

storage backup: duplicity to NFS share, duplicity to VTLUUG, etc.

Mail transfer

set up two MTA servers (at most one in the lounge), each with its own MDA and MSS.

configure BIND to broadcast two mx records (multihomed A record?)

Mail delivery

configure one MDA for each MTA server.

MDA shall deliver to a Maildir located under a mounted Tahoe-LAFS share.

MDA delivers mail to corresponding user in LDAP.

configure LDAP on each server and sync/replicate the entire directory periodically.

Online storage

Use the traditional Maildir format for storing mail. Make the MDA/LDA store it under the Tahoe-LAFS $BASEDIR directory on the mail server so it can be accessed from multiple different MSSs and MUAs. Set up Tahoe-LAFS "dumb" storage servers at the mail site and the lounge. Configure additional storage servers wherever possible (e.g. members can volunteer their server). Tahoe-LAFS storage servers contain only encrypted data, so it doesn't matter who volunteers their space. Only the Tahoe-LAFS gateways (MSS and MUA servers) can decrypt the mails and securely hand them to authenticated/authorized users.

Offline storage

Occasionally copy the Maildir directory out of the Tahoe-LAFS share since we don't actually trust Tahoe-LAFS. We respect people's privacy, so don't just rsync it out to a 3rd party. Easiest solution would be to use Duplicity to automatically perform encrypted, incremental backups to the 3rd party.